Carrier Ethernet is evolving to support the needs of the carrier network environment. Carrier Ethernet requires scalable, reliable, and dynamic mechanisms to support operations, administration, and management (OAM) and traffic engineering (TE). Standards have been developed in the Metro Ethernet Forum (MEF), International Telecommunication Union (ITU), Institute of Electrical and Electronics Engineers (IEEE), and the like providing many of these required extensions. Specifically, Connectivity Fault Management (CFM) is an Ethernet standard to provide many common OAM functions associated with underlying network transport for services. For example, CFM is defined in IEEE 802.1ag-2007 IEEE Standard for Local and Metropolitan Area Networks Virtual Bridged Local Area Networks Amendment 5: Connectivity Fault Management, the contents of which are herein incorporated by reference. Also, OAM functions are also defined in ITU-T G.8013/Y.1731 (July 2011) “OAM functions and mechanisms for Ethernet based networks,” the contents of which are herein incorporated by reference. Further, the MEF also defines Ethernet OAM in various technical specifications, such as MEF 17 (April 2007) “Service OAM Requirements & Framework,” the contents of which are herein incorporated by reference. Variously, CFM enables definition of maintenance domains, their constituent maintenance points, and the managed objects required to create and administer them; definition of relationships between maintenance domains and the services offered by Virtual Local Area Network (VLAN)-aware bridges and provider bridges; description of protocols and procedures used by maintenance points to maintain and diagnose connectivity faults within a maintenance domain; and the like.
IEEE 802.3ad Link aggregation (or trunking) is a method of combining multiple physical Ethernet links into a single logical link for increased performance. LAG (Link Aggregation) ports are widely used for client handoff in Layer 2 (L2) networks because of ease of service scalability on live network. Ethernet private line (EPL) are carrier Ethernet data services defined by the Metro Ethernet Forum (MEF). EPL provides a point-to-point Ethernet virtual connection (EVC) between a pair of dedicated user—network interfaces (UNIs), with a high degree of transparency. In the case of EPL services having a LAG on either or both UNI terminations, a change in LAG operational speed due to a link failure or additional/removal of LAG member ports remains unnoticed by a far end L2 switch and Customer premises equipment (CPE). This leads to an operational speed mismatch between terminating UNIs which consequently leads to silent traffic losses on the L2 switch. There are known mechanisms such as Link Loss Forwarding, etc. to propagate UNI link status failures to the far end, enabling action on these notifications for EPL services. Conventionally, there is no solution available to address silent traffic loss because of LAG UNI operational speed changes due to a link/Link Aggregation Control Protocol (LACP) failure on a few but not all LAG members. In these cases, on LAG UNI-based EPL services, LAG operational speed reduction (because of run-time LAG distribution changes) at the near end UNI remains unnoticed to the far end UNI termination and vice versa. Consequently the near end, operating at a lower speed now, would start dropping traffic coming from the far end UNI. This failure is silent to the far end.